Within the last one hundred years, petroleum has become the overwhelming primary commodity as an organic raw material. Petroleum has had the advantages of low cost and ease of transportation and storage because of its liquid consistency. Further, petroleum is readily amenable to fractionation and conversion into a variety of valuable industrial products such as fuels, building products, chemical intermediates, and the like.
Recent international economic developments have signaled the inevitable decline of petroleum as the world's supreme industrial commodity. The price of raw petroleum has increased several fold. Also, the consumption of petroleum has been increasing exponentially and concomitantly the world petroleum supply has diminished to less than several decades of proven reserves.
Governments and industries on a priority basis are dedicating increased attention to alternatives to petroleum as sources for fuels and chemical intermediates, e.g., substantial reserves of coal exist in highly industrialized countries.
It was recognized by early workers that coal can be liquified by controlled heating in the substantial absence of oxygen. The conversion products are a liquid and a char. Because of the new compelling economic factors, the technology of coal liquefaction and gasification has been expanding at an accelerated pace. Pioneer developments in the field are represented by Lurgi and Fischer-Tropsch technology. More recent advances in coal liquefaction are described in U.S. Pat. Nos. 1,904,586; 1,955,041; 1,996,009; 2,091,354; 2,174,184; 2,714,086; 3,375,188; 3,379,638; 3,607,718; 3,640,816; 3,642,608; 3,705,092; 3,849,287 3,870,621; inter alia.
One of the new developments in Fischer-Tropsch technology, i.e, the Sasol process, has been expanded into a commercial venture for converting low grade coal into synthesis gas, and a broad spectrum of organic derivatives such as fuel gas, light olefins, LPG, gasoline, light and heavy fuel oils, waxy oils, and oxygenated chemicals such as alcohols, ketones and acids. A byproduct of the Sasol commercial operation is coal tar. The formation of coal tar byproduct affects the economics of the Sasol operation, and the increasing accumulation of this byproduct stream has environmental implications.
There remains a pressing need for new technology for the conversion of coal into carbonaceous products which complement and enhance conventional petroleum derived industrial applications. Innovative processes are required for upgrading poor quality coal and coal byproducts into commodity materials.
Further, the phenomenon of world population growth and the competition for limited natural resources have compelled governmental agencies and the academic and business communities to initiate and promulgate programs for the conservation of natural resources and the stabilization of ecological factors. Reclaiming and recycling of expended commodities has become an overriding consideration in progressive legislation for environmental protection and control of natural resource exploitation.
Accordingly, it is an object of the present invention to provide novel manufactured petroleum products which contain substantial quantities of organic components which are not petroleum-derived raw materials.
It is another object of the present invention to upgrade low value petroleum byproduct streams from refinery operations into valuable commercial products.
It is another object of the present invention to provide a process for producing asphaltic products which contain a substantial quantity of recycled waste materials.
It is a further object of the present invention to provide an economically attractive process for converting coal tar into paving grade ashalt.
Other objects and advantages of the present invention shall become apparent from the accompanying description and examples.